A jaw of the above-mentioned type is described for example in Austrian Pat. No. 315 041. The movable part of this construction is designed in the form of a rack as a body of revolution with at least one rotating groove, and is supported movably in the longitudinal center plane of the jaw between the bolts of the sole holder, so that extensions on the sole holders engage the grooves of the rack. If a lateral force acts onto a clamped-in ski shoe, then both sole holders swing outwardly and the rack is hereby pulled backwardly by the extensions against the force of the spring. An important disadvantage of this conventional construction is that high frictional forces occur between the ski shoe sole and the sole holder when forces act on the sole holder in a direction toward the tip of the ski, as occurs for example during a forward fall of the skier, which frictional forces delay or prevent a release of the jaw and can thus cause injuries to the skier.
The purpose of the invention is to bring help here and to provide a jaw of the above-mentioned type which compensates for the frictional forces which occur when a force acts on the jaw in a direction toward the tip of the ski, so that the release force is preferably maintained substantially constant.